This invention relates to turbulence producing and flow mixing devices for incorporation in pipes and other ducts so as to promote mixing of materials, chemical reactions, or heat exchange through the pipe wall. The invention is herein illustratively described by reference to the presently preferred embodiments thereof; however, it will be recognized that certain modifications and changes therein with respect to details may be made without departing from the essential features involved.
Streams of materials flowing in pipes or ducts may include components that are solid, liquid or gaseous, or combinations thereof. They may have characteristics which allow or require chemical reactions one with another or simply mixing. In some cases the objective of creating turbulence is simply to promote the exchange of heat between the material flowing in the pipe and a medium surrounding the pipe or comprising the pipe wall itself, for that matter. A broad object of this invention is to devise a stationary means that can be mounted within a pipe or other duct to create special turbulence flow patterns therein as to maximize the degree of mixing or the degree of heat transfer to or from the material; more specifically to promote positional interchanges of material flowing along the region adjacent the pipe wall with material flowing along the central region within the pipe and of achieving this without unnecessarily impeding flow through the pipe.
A related object is to promote uniformity and thoroughness of mixing and/or heat transfer in a relatively short length section of pipe incorporating one or more sets of the cooperating flow dividers.
Previous designs of systems that have been utilized to create turbulence or mixing in pipes tend to be bulky and space consuming for the amount of turbulence or mixing effect achieved. In addition, they tend to produce excessive pressure drops along the pipe run for the amount of mixing or heat transfer created. Prior art of varying background interest in relation to this invention is represented by disclosures in the following United States patents:
______________________________________ 3,652,061 Chisholm 3,286,992 Armeniades, et al 3,404,869 Harder 3,583,678 Harder 3,664,638 Grout, et al 3,704,006 Grout, et al ______________________________________
There are a number of applications for this invention in industrial processes. For example, in some cases it is desirable to create uniform dispersion of insoluble gases or partially soluble gases in a fluid stream flowing in a pipe in order to promote chemical reactions or absorption of the gas. In other cases, one or more liquids and solid particles are to be mixed or the particles are to be dissolved in the liquids, with or without attendant chemical reaction. In still other cases, premixed materials are to be reacted during flow, with or without promotion or retardation of the reaction process due to application of heat or withdrawal of heat from the materials. In such cases, the invention is useful in accelerating and promoting uniformity in the rate of mixing, reacting and/or heat addition or withdrawal from the mixture by transfer through the pipe wall.
A further object of this invention is to provide a compact and efficient means for admixing two or more components of flow in a stream of material, or for promoting turbulence for other purposes, such as for heat exchange purposes.
A further object is to devise such a device that promotes the exchange of positions of medium flowing in the pipe such that the material adjacent the pipe wall is exchanged with the material flowing near the pipe axis, back and forth in all directions as the flow progresses through the pipe past the turbulence creating sets of flow dividers.